In situ chemical oxidation (ISCO) using permanganate (MnO4) can be effective for in situ treatment of chlorinated ethenes and other groundwater contaminants if the MnO4 contacts the target contaminant. There are a variety of different approaches that can be used to distribute MnO4 in the subsurface including: (a) injection only using grids of temporary or permanent wells; and (b) recirculation using systems of injection and pumping wells. Each of these approaches has advantages and disadvantages with the best approach dependent on site-specific conditions. For each approach, cost and effectiveness are a function of the well layout and injection sequence. Consequently, the optimum design will include a specific arrangement of wells, injection volumes and rates, and amount of reagent. Existing guidance documents (ITRC 2005, and Huling and Pivetz 2006) provide general information on how the remediation process works and factors to consider when planning an injection system. However, these documents do not provide specific information on how to actually design an injection system to provide good amendment distribution at a reasonable cost.